Heat Sink Adaptor

ABSTRACT

An adaptor is provided for use with the heat sink, said heat sink comprising a base for contacting a heat source and a plurality of protrusions extending from said base. The adaptor itself comprises a base and a structure projecting therefrom. The structure is arranged to mate with one or more protrusions on the heat sink to enable heat transfer by conduction from the heat sink to the adaptor.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of British Patent Application No. GB1112598.6 filed on Jul. 21, 2011, the entire disclosure of which isincorporated herein by reference.

FIELD

The invention relates to an adaptor for a heat sink.

BACKGROUND

Heat sinks are well known devices that are used in a range of industriesfor cooling other devices that generate high temperatures. The term“heat sink” is generally used to describe any component or apparatusthat transfers heat generated within a solid device to a fluid such as aliquid or air by convection. Heat sinks are used in refrigeration andair conditioning systems as well as for cooling a range of electronicand opto-electronic devices including computer central processing units(CPU's) and other processors.

FIG. 1 shows a typical heat sink 100. It comprises a base 102 and aseries of fins 104 projecting outwardly therefrom. In the heat sink 100shown in FIG. 1, the fins 104 project substantially perpendicularly froman upper face of the base 102. Each fin 104 is relatively thin so that aplurality of fins 104 can be arranged on the upper face of the base 102with a gap between adjacent fins 104. Each fin 104 comprises first andsecond large substantially flat faces opposite one another. In FIG. 1the large faces are substantially rectangular.

Other configurations of heat sink that differ from the one shown in FIG.1 are well known. For example the fins in a heat sink may not projectsubstantially perpendicularly from the base. They may instead project atdifferent angles to create a flared or fanned fin arrangement.Alternatively or additionally, a plurality of pins may be used toreplace the essentially planar fins shown in FIG. 1. In general, thepurpose of the fins or pins in a heat sink is to create as large asurface area as possible within a given volume. That surface area isused for heat transfer from the heat sink to a surrounding fluid.

In operation, the base of a heat sink is placed in contact with a devicethat acts as a heat source and generates high temperatures, from whichheat is to be directed away. The base can be placed in direct physicalcontact with the heat source. Optionally, a thermal adhesive or thermalgrease may be added to the base of the heat sink to improve its thermalperformance. Heat is conducted away from the heat source into the baseand through the fins of the heat sink. That heat can then travel byconvection from the heat sink to the surrounding fluid. The increasedsurface area of the fins aids transfer of heat to the surrounding fluid.Furthermore, the heat transfer by convection to the surrounding fluidcan be enhanced by flow of the fluid around the heat sink, in particularin the gaps between the fins of the heat sink. Fluid can be forcedbetween the fins of a heat sink, for example using a fan.

Whilst existing heat sinks are widely utilised and can be very useful incooling heat generating devices, they are nonetheless limited to coolingby thermal convection. They are unable to operate in any other coolingmode without significant changes being made to their fundamental design.Cooling systems which include a heat sink are difficult to configure foruse in different modes of operation without replacement of the heatsink. Therefore the range of suitable applications for conventional heatsinks is limited.

For example, conventional heat sinks are unsuitable for use inenvironments where the air used to provide ‘forced air cooling’ containparticulates (wood, stone, fibres etc.), as such particulates are likelyto clog the fan circulating the air and the fins of the heat sink overtime, reducing the efficiency of the heat sink. They also conventionallyare unsuitable for use in environments where a high degree of protectionis required from water, gas or dust as this necessitates installation ofthe heat sink in a sealed enclosure, limiting the supply of cool air tosupply to the heat sink and thus reducing its efficiency.

SUMMARY

According to an aspect there is provided an adaptor for use with a heatsink, said heat sink comprising a base for contacting a heat source anda plurality of protrusions extending from said base. The adaptor itselfcomprises a base and a structure projecting from that base wherein thestructure is arranged to mate with one or more protrusions on a heatsink to enable heat transfer by conduction from the heat sink to theadaptor. Preferably at least one surface of the structure on the adaptorcan come into direct contact with a surface of a protrusion on the heatsink in order to enable the heat transfer by conduction from the heatsink to the adaptor. The structure may comprise projections, fins orpins extending from the base of the adaptor. Alternatively the structuremay be substantially solid with recesses or channels therein into whichprotrusions on a heat sink can insert. The adaptor can channel heatwhich it collects from a heat sink to another location or cooling systemby a range of different heat transfer means.

According to an aspect there is provided a cooling system for a heatsource. The cooling system includes a heat sink comprising a base forcontacting the heat source and channelling heat away therefrom as wellas a plurality of protrusions extending from said base of the heat sink.The cooling system further comprises an adaptor comprising a base and astructure projecting from the base wherein the structure on the adaptoris arranged to mate with one or more of the protrusions on the heat sinkto enable heat transfer by conduction from the heat sink to the adaptor.

According to another aspect there is provided a method of adapting aheat sink, said heat sink comprising a base for contacting a heat sourceand a plurality of protrusions extending from that base. The methodcomprises fitting an adaptor to the heat sink wherein that adaptorcomprises a base and a structure projecting from said base. When theadaptor is fitted to the heat sink the structure on the adaptor is matedwith one or more of the protrusions on the heat sink to enable heattransfer by conduction from the heat sink to the adaptor. Heat can thenbe channelled away from the adaptor using any suitable heat transfertechnique.

According to another aspect there is provided a method of transferringheat away from a heat source. The method comprises putting a heat sinkin contact with the heat source, said heat sink comprising a base forcontacting the heat source and a plurality of protrusions extending fromsaid base. The method further comprises fitting an adaptor to the heatsink wherein the adaptor comprises a base and a structure projectingfrom said base wherein fitting the adaptor to the heat sink includesmating the structure on the adaptor with one or more of the protrusionson the heat sink to enable heat transfer by conduction from the heatsink to the adaptor. Optionally the method may also comprise bringingthe base of the adaptor, which is distal to the heat source when theheat sink is in contact therewith, into connection with an externalcomponent. That external component may be a cooling device.

FIGURES

Embodiments and examples will now be described with respect to theappended figures of which:

FIG. 1 shows an example of an existing finned heat sink;

FIG. 2 shows an example of a heat sink adaptor for use in conjunctionwith the heat sink of FIG. 1;

FIG. 3 shows the adaptor of FIG. 2 in connection with a heat sink; and

FIG. 4 shows a plan view of the adaptor of FIG. 2 in connection with aheat sink.

OVERVIEW

In overview there is provided an adaptor for use with a heat sink. Inparticular the adaptor can be used with a finned heat sink. The adaptormates with the heat sink to enable heat transfer by conduction from theheat sink into the adaptor. Preferably at least one surface of theadaptor should directly contact a surface of the heat sink to enablesuch conduction. Increasing the size of the surface area over which theadaptor directly contacts the heat sink increases the extent of heattransfer therebetween. The adaptor has a structure which can includefins or other projections that insert into the gaps between protrusionssuch as fins on a heat sink so that heat can travel from thoseprotrusions into the adaptor.

The physical configuration of the adaptor is largely dictated by thephysical size and shape of the heat sink with which it is to be used.The adaptor must be able to mate with the heat sink and preferably itshould be possible to lock the adaptor and heat sink together. At itsdistal end, away from the heat source which contacts the heat sink, theadaptor has a base. Preferably the outermost face of the base issubstantially flat. Such an arrangement enables the adaptor to beconnected to other external components such as other cooling devices.The adaptor may also comprise built-in cooling or heat transfercomponents such as liquid filled pipes.

DETAILED DESCRIPTION

The heat sink adaptor disclosed herein can be better understood withrespect to the figures. As discussed above in the background section,FIG. 1 shows a typical existing finned heat sink 100. FIG. 2 shows sucha heat sink aligned with an adaptor 200 for use therewith.

The adaptor 200 shown in FIG. 2 comprises a base 202 and a series offins or other projections 204 extending therefrom. In the adaptor shownin FIG. 2 the projections 204 extend substantially perpendicularly froma face of the base 202. Each projection 204 is substantially rectangularin cross section and is relatively thin, with two large faces oppositeone another, similar to the fins 104 described above with respect to theknown heat sink 100. Because the adaptor 200 shown in FIG. 2 is for usewith an existing finned heat sink such as the one shown in FIG. 1, thethickness of the projections 204 therein should ideally be sized to fitinto the gaps between adjacent fins 104 in the heat sink 100. This canfurther be understood from FIGS. 3 and 4 which show the adaptor 200 inconnection with the heat sink 100.

The adaptor 200 can include enough projections 204, appropriately sizedand spaced, as to fit into every other gap between fins 104 in the heatsink 100, as shown in FIGS. 2 to 4. This ‘every other’ fin arrangementbetween the heat sink 100 and the adaptor 200 allows for the fins 104 ofthe heat sink 100 to move slightly as they receive the approachingprojection 204 from the adaptor. Alternatively the adaptor 200 couldhave enough projections 204 as to fit into every gap between fins 104 inthe heat sink 100 or only to fit into some of the gaps.

The projections 204 in one embodiment provide a friction fit between theadaptor 200 and a heat sink 100 to ensure good surface area contact. Anysuitable configuration of the projections 204 could be implemented,provided sufficient surface area contact is ensured between the heatsink 100 and the adaptor 200 to allow the adaptor 200 to conduct enoughheat from the heat sink 100 for a given situation.

The adaptor 200 can be aligned with the fins of a heat sink 100 as shownin FIG. 2 and inserted into the heat sink 100 as shown in FIGS. 3 and 4to form a mating connection. The heat sink 100 and adaptor 200 combineto form a cooling system.

According to an embodiment, when the adaptor 200 is mated with the heatsink it will not occupy all of the gaps between the fins of the heatsink, so that there will still be some space for air or other fluid toflow through the cooling system. This allows the cooling system to coolat least partially using convection and so not rely entirely onconduction of heat from the heat sink 100 to the adaptor 200 in order todirect heat away from the heat sink 100.

The faces of the projections 204 on the adaptor 200 should fit asclosely as possible to the respective fins 104 of the heat sink, viawhich heat is conducted out of the heat sink into the adaptor 200. Theshape and orientation of the projections 204 on the adaptor 200 shouldalso be matched as closely as possible with the shape and orientation ofthe fins 104 of the heat sink so that the adaptor 200 and heat sink canfit together easily and so that a large common surface area is providedfor conduction of heat from the fins 104 of the heat sink to theprojections 204 of the adaptor 200.

The adaptor 200 should be designed to provide as large a contact surfaceas possible for the heat sink with which it is to be used, to maximiseheat transfer by conduction from the heat sink to the adaptor 200. Forexample, as shown in FIG. 4, the adaptor 200 shown in FIGS. 2 and 3provides three contact surfaces for each fin 104 of the heat sink, viawhich heat can travel by conduction into the adaptor 200 out of the heatsink.

As shown in FIG. 3, the adaptor 200 can be fixed to the heat sink 100 byany suitable means such as bolts 206. The method of attachment shouldpreferably be temporary, i.e. reversible, rather than permanent so thatthe adaptor 200 can be fitted to an existing heat sink when appropriatefor certain applications and removed therefrom at other times withoutrequiring any significant adaptation of either device. According to anembodiment, screws are used for fixing the adaptor 200 to the heat sinkwherein the thread of the screw can form a thread in the walls of thefins of the heat sink during insertion.

In addition to the projections 204 described above, the adaptor 200 asshown in FIGS. 2 to 4 comprises a base 202. Each of the projections 204terminates at the base 202 therefore the majority of the heat which isconducted into the adaptor 200 from the heat sink will be directedtowards the base 202. As shown in FIG. 4, ideally the base 202 shouldhave a substantially flat outer face, opposite the face from which theprojections 204 extend. That substantially flat face can act as a flatsurface for contact between the adaptor 200 and an external componentsuch as a cooling device. Or another type of physical connection can bemade between the adaptor 200 and the cooling device. For example thatcooling device could be a water cooled heat sink, an air cooled plate ora “cold plate” cooling device. As is known in the art, such coolingdevices cannot be used in direct contact with a conventional heat sinksuch as the one shown in FIG. 1 which transfers heat by convention tofluid only. However if an adaptor 200 such as the one shown in FIGS. 2to 4 is used in conjunction with a conventional heat sink, intermediatethe heat sink and the cooling device, those cooling devices (and othercomponents) can be successfully used in conjunction with theconventional heat sink without having to permanently alter the design ofeither the heat sink or the cooling device itself. Therefore the adaptorincreases the usefulness of the heat sink and the range of applicationsfor which it can be used.

As well as being able to connect to external cooling devices fordirecting heat away therefrom, the adaptor 200 can include built incomponents to manage the removal of heat that the adaptor 200 collectsfrom the heat sink. According to an embodiment, one or more pipes isembedded within the adaptor 200. The pipes can contain liquid or otherfluid which can flow through the pipes out of the adaptor 200, therebyremoving the heat therefrom. An arrangement of pipes within the adaptor200 may also be part of a gas compression system to provide cooling dueto fluid phase change. The energy requirements of a phase change from aliquid to a gas within the pipes efficiently draws heat away from theadaptor.

For situations where the product to be cooled must be contained within asealed enclosure, the heat sink adaptor can provide a physical cooling‘bridge’ to the outside of the enclosure where a greater supply of air,liquid or other cooling medium can be available.

The adaptor 200 may be fabricated from any suitable material orcombination of materials. The material(s) should offer good thermalconductivity. For example the adaptor may comprise aluminium, copper,other ferrous or non-ferrous metals or glass.

The particular adaptor described above and shown in FIGS. 2 to 4 is acold plate adaptor which is designed to fit with a finned heat sink asshown in FIG. 1 which has substantially rectangular fins extendinggenerally at a right angle from a base of the heat sink. However otheradaptors can be designed and can operate according to the sameprinciples in conjunction with other designs of heat sink. For exampleif the heat sink has flared or irregularly angled fins projecting fromits base, the size, shape and orientation of the projections of theadaptor can be appropriately configured to match the flared orirregularly angled fins, so that the projections fit well into the gapsbetween adjacent fins and have a large amount of surface area in commonwith the fins to provide thermal contact surfaces for conduction of heatfrom the heat sink to the adaptor. Similarly, if the heat sink comprisesanother type of protrusion, for example pins extending from the base,the adaptor can include suitably sized and shaped projections to matchthose protrusions. For example cylindrical projections, into which thepins of the heat sink can insert for conduction of heat from the heatsink to the adaptor, can be provided. Alternatively, the adaptor couldcomprise a substantially solid block with slots or channels therein intowhich the protrusions from the heat sink can insert.

As mentioned above, the base of the adaptor can be fitted to or canotherwise contact an external component such as another cooling devicein any appropriate manner. For example, pipes or other conduits may beused to transfer heat from the adaptor 200 to an air cooled heat sinksomewhere else, a water cooled system, a condensed gas system or anyother suitable cooling device. As a result, a conventional heat sink(when used with the adaptor 200) can be more versatile. For example,instead of using forced air for cooling a conventional heat sink inenvironments where the air used contains particulates that are likely toclog the fins over time and thus reduce efficiency of the heat sink, theadaptor can be mated into the gaps between the fins of the heat sink andused to channel heat away from the heat sink, without needing to forceparticle-filled air around the heat sink. And in environments where ahigh degree of protection is required from water, gas or dustnecessitating installation of the heat sink in a sealed enclosure,limiting the supply of cool air to supply to the heat sink and soreducing its efficiency, the adaptor can be used to remove heat from theheat sink using conduction instead of convection and channel itelsewhere without replacing the existing heat sink.

So it can be seen that the adaptor is highly useful for updatingexisting cooling systems which rely on conventional heat sinks andmaking them more useful and efficient without having to replace the heatsink. Therefore the adaptor is a cost effective solution which avoidsphysical disruption to existing systems. It can also be convenientlymanufactured in conjunction with a new heat sink, hence increasing theheat sink's potential usefulness. The adaptor can include internalcooling components and/or can connect to external cooling components todirect heat away from the heat sink and associated heat source in anysuitable manner, depending on the particular application or environmentin which it is to be used. Therefore the adaptor enables an existingdevice which includes a heat sink to be used in a wider range ofenvironments.

Whilst some specific examples of the uses of heat sinks have been givenabove, the adaptor described herein can be used in conjunction with aheat sink for any appropriate application in which heat must betransferred away from the heat source. The adaptor can be of anysuitable size, shape and configuration in order cooperate with the heatsink physically and to meet the requirements for thermal transfertherefrom. The adaptor can be designed, manufactured and/or suppliedwith a co-operating heat sink, or can be retrofitted to an existing heatsink. By enabling heat to be conducted out of a conventional heat sink,rather than relying on convection, and by doing so in a simple andstraightforward manner which does not require permanent adaptation ofthe existing heat sink, a highly useful and practical solution isprovided by the adaptor.

1. An adaptor (200) for use with a heat sink, said heat sink comprisinga base for contacting a heat source and a plurality of protrusionsextending from said base, wherein said adaptor (200) comprises: a base(202); and a structure (204) projecting from said base (202); whereinsaid structure (204) is arranged to mate with one or more protrusions ona heat sink to enable heat transfer by conduction from the heat sink tothe adaptor (200).
 2. An adaptor (200) as claimed in claim 1 whereinsaid structure (204) comprises a plurality of projections extending fromsaid base (202) of the adaptor (200).
 3. An adaptor (200) as claimed inclaim 2 wherein said projections (204) comprise fins.
 4. An adaptor(200) as claimed in claim 3 wherein said fins (204) are substantiallyrectangular in cross section.
 5. An adaptor (200) as claimed in claim 2wherein said projections (204) extend substantially perpendicularly froma face of said base (202).
 6. An adaptor (200) as claimed in claim 2wherein the projections (204) extend from a face of said base (202) in aflared arrangement.
 7. An adaptor (200) as claimed in claim 1 wherein atleast one surface of the structure (204) is arrange to contact at leastone surface of the plurality of protrusions extending from the base ofheat sink, to enable heat conduction from the heat sink to the adaptor(200).
 8. An adaptor as claimed in claim 2 wherein at least one of saidprojections (204) is arranged to fit into a gap between adjacentprotrusions on a heat sink, to provide a mating fit between the heatsink and the adaptor (200).
 9. An adaptor (200) as claimed in claim 1wherein said adaptor further comprises a built in cooling component. 10.An adaptor (200) as claimed in claim 9 wherein said built in coolingcomponent comprises a fluid filled conduit.
 11. An adaptor (200) asclaimed in claim 1 wherein said base (202) is arranged to connect to anexternal cooling component for heat transfer from the adaptor (200) tosaid external cooling component.
 12. A cooling system for a heat source,said cooling system including: a heat sink (100) comprising a base (102)for contacting the heat source and a plurality of protrusions (104)extending from said base (102); and an adaptor (200) as claimed in claim1 in mating contact with said heat sink (100).
 13. A method of adaptinga heat sink (100), said heat sink (100) comprising a base (102) forcontacting a heat source and a plurality of protrusions (104) extendingfrom said base (102), wherein said method comprises fitting an adaptor(200) to the heat sink (100), said adaptor (200) comprising a base (202)and a structure (204) projecting from said base (202), wherein saidfitting includes mating the structure (204) on the adaptor (200) withone or more protrusions (104) on the heat sink (100) to enable heattransfer by conduction from the heat sink (100) to the adaptor (200).14. A method as claimed in claim 13 wherein the step of mating thestructure (204) on the adaptor (200) with one or more protrusions (104)on the heat sink (100) comprises bringing at least one surface of thestructure (204) into contact with at least one surface of the pluralityof protrusions (104).
 15. A method as claimed in claim 13 wherein thestructure (204) on the adaptor (200) comprises a plurality ofprojections and wherein the step of mating said structure (204) with oneor more protrusions (104) on the heat sink (100) comprises inserting atleast one of said plurality of projections into a gap between adjacentprotrusions (104) on the heat sink (100).
 16. A method as claimed inclaim 15 wherein said at least one projection (204) is sized and shapedso that, when it is inserted into said gap between adjacent protrusions(104) on the heat sink (100), an upper surface of the projection (204)comes into contact with the base of the heat sink (100).
 17. A method asclaimed in claim 15 wherein said at least one projection (204) is sizedand shaped so that, when it is inserted into said gap between adjacentprotrusions (104) on the heat sink (100), a side surface of theprojection (204) comes into contact with a side surface of one of saidadjacent protrusions (104) on the heat sink (100).
 18. A method asclaimed in claim 13 further comprising connecting said adaptor (204) toan external cooling component for transfer of heat from the adaptor(200) to said external cooling component.